I place them in the same tier but expect Zoro to win a fight due to superior stamina and endurance. Bullet to my head, I'd also bet Zoro's strongest attacks are superior to Old Rayleigh's strongest attacks (alternatively, Pizarro tanked a Haoshoku coating attack from Old Garp, but if it was Zoro instead, he'd definitely be dead).
I don't think current Rayleigh can pull of Dragon Damnation level attacks.
Old Rayleigh probably has better COO, and maybe better reactions, but Zoro's endurance can plug that gap I think.
But even if he could I'd expect Zoro to outlast him.
As for the Lucci fight, Zoro isn't going all out here yet.
Luffy used Gear 5 to put Awakened Lucci down and even then still needed 4/5 attacks.
I don't think it's an anti-feat for Zoro that he uses his COA to deal with Lucci.
It shows that Zoro's taking him seriously.
Unless Borsalino decisively demonstrates superiority to Gear 5 Luffy without Awakening, I'd still expect current Zoro to beat Old Rayleigh due to greater haki and physical stamina.
Or alternatively if Zoro needs to use Haoshoku coating for more than one attack vs Awakened Lucci, I'll bump him below the old legends.